As the virus mutates, giving birth to viral offspring called quasispecies, it presents an ever-changing face to the immune system, which is continually adapting itself to keep up with the onslaught. The immune system does a remarkable job fending off the assault, killing most of the viral particles every day. Even so, some of the virus is able to elude the body's defenses and ultimately devastates the immune system in most patients.

(Good review of the PLoS article, except for the fact that they write that HIV "develops" resistance when they mean "evolves.")

This is the second post in the Ignore-the-science-pay-the-price series. First.

Pleiotropy comes from the Greek πλείων pleion, meaning "more", and τρέπειν trepein, meaning "to turn, to convert". It designates the occurrence of a single gene affecting multiple traits, and is a hugely important concept in evolutionary biology.

I'm a postdoc at UC Santa Barbara.

All Many aspects of evolution interest me, but my research focus is currently on microbial evolution, adaptive radiation, speciation, fitness landscapes, epistasis, and the influence of genetic architecture on adaptation and speciation.